Laser induced fluorescence from theAthinsp;2Pgr;i(v= 0) state of CO+

摘要

A pulsed, tunable dye laser is used to obtain either the excitation spectrum for theAthinsp;2Pgr;indash;Xthinsp;2Sgr;+thinsp;(0,0) band of CO+, or the time resolved fluorescence from individual rotational levels of the upper state for this transition. The ions are formed by reacting CO with helium metastable atoms produced in a dc discharge. Although the rotational structure of theAthinsp;2Pgr;ithinsp;(v= 0) state is well known from numerous studies of the emission spectra of CO+, our laser excitation spectrum reveals perturbations in this state which have not been reported previously. rsquo;rsquo;Extrarsquo;rsquo; lines are observed in theR21andQ22branches of theAthinsp;2Pgr;1/2ndash;Xthinsp;2Sgr;+thinsp;(0,0) subhyphen;band and are associated with theehyphen;parity rotational levels of theAthinsp;2Pgr;1/2spin component havingJvalues of 2.5, 3.5, 4.5, 5.5, 6.5, and 7.5. The perturbing levels which are the source of these rsquo;rsquo;extrarsquo;rsquo; lines are theeparity orF1spin components of theXthinsp;2Sgr;+(v= 10) state having the sameJvalues. Perturbation matrix elements and wave function mixing fractions are determined from the experimental data. The molecular constants of the interacting states are deduced and a discussion is given on the effect of these perturbations on the time resolved fluorescence from individual rovibronic levels of theAthinsp;2Pgr;i(v= 0) state.